1. Field of the Invention
The present invention relates to an image capturing apparatus and a method for controlling the image capturing apparatus, and in particular to an image capturing apparatus that suppresses color deviation resulting from noise due to temperature and exposure time, and a method for controlling the image capturing apparatus.
2. Description of the Related Art
In conventional image capturing apparatuses, suppression of noise due to gain, temperature and exposure time, and white balance (WB) correction are controlled.
Such suppression control of noise due to gain is described in, for example, Japanese Patent Laid-Open No. 5-91402, in which, when video signals obtained by an image sensing element are displayed, noise components of a color signal of the video signals are suppressed on the basis of information on the gain determined based on a photometric value.
Further, Japanese Patent Laid-Open No. 2010-273319 discloses that a captured image is divided into sub-regions, and for each sub-region and each color component, a standard deviation of image signals in each pixel is calculated, and a region in the captured image which is subjected to the calculation of a WB gain is extracted on the basis of a comparison result between the calculated standard deviation and a noise model.
Although there are cases where noise causes color deviation depending on temperature and exposure time, and an image with colors different from those of the actual object results, the conventional techniques such as Japanese Patent Laid-Open Nos. 5-91402 and 2010-273319 have not corrected the color deviation caused by noise.